RE: "Reliable" web services for Next Big Thing? (was RE: Agenda for 5 December WSA telcon)

> Yup. This is another one of those densely interconnected
> clusters of issues (sortof like "choreography"): "Asynchrony"
> is associated with it (without a reliable substrate, senders
> and receivers can talk "out of band" to ensure that messages
> were received), it's tangled up with Coordination and Transactions
> because Web service invocations can fail for all sorts of reasons
> besides messages not being delivered

One aspect that intrigues me in this area is the fact that the general subject of reliability has been directly connected so far to the use of proprietary infrastructures like MQSeries and MSMQ (which also touch on all the different items you mention above). What intrigues me is the possibility that a standards-based approach like Web services on HTTP could be as effective as one of those proprietary solutions.

What I heard many times from vendors of these proprietary solutions is the following: yes, you can use Web services on HTTP, but if you require additional QoS like reliable messaging you'd better run your Web services on top of one of those proprietary frameworks. (The recent interest in running SOAP over JMS - even within Apache Axis - is a manifestation of that trend). But this approach complicates things because then you have to support gateways to switch from Web services on the Internet (over HTTP) to Web services on the Intranet (over proprietary protocol).

Surprisingly enough, Microsoft's MSMQ 3.0 supports something along the lines of what I have been thinking. You can choose a version of MSMQ 3.0 which runs on top of SOAP and HTTP, and which has the same reliability properties as the traditional MSMQ over proprietary protocol. Kind of the idea of SOAP over JMS, but turned upside down. But I am not sure whether this particular version of MSMQ is just a publicity stunt, or it can actually compete with the other proprietary version.

Another interesting area of discussion on the subject of reliable Web services is whether to go with a reliable underlying protocol (e.g. IBM's HTTPR) or with reliability information included in SOAP headers (e.g. Microsoft's SRMP).

Ugo

Received on Thursday, 5 December 2002 12:19:08 UTC